Combined telegraph and telephone signaling system



Dec. 7 1926. 1,609,881

7 F. B. PHILBRICK COMBINED TELEGRAPH AND TELEPHONE SIGNALING SYSTEM Filed D90. 4, 1924 4 ii 6 ;85' 52 M :AnAAAn l 721 other Boxes x in series I I I I I I n L L I mvENT oR 70 027167 M/j Frederick E, Philbrick siai'z'ans in s ries BY 6.65? M ATTORN EY Patented Dec. 7, 1926.

UNITED STATES FREDERICK B. PI-IILBRICK, (3F W'EST NEWTON,

GAMEWELL COMPANY, OF NEWTON UPPER FALLS, MASSACHUSETTS, A CORPORA- TION OF MASSACHUSETTS.

COMBINED TELEGRAPH AND TELEPHONE SIGNALING SYSTEM.

Application filed December 4, 1924. Serial No. 753,883.

This invention relates to combined telegraph and telephone signaling systems and is particularly adapted for embodiment 1n so-called emergency signaling systems such, for example, as municipal fire alarm systems; in which one or more circuits are provided, each serially connecting a headquarters or main station and a plurality of sub-stations, some of which sub-stations are equipped with signal formulating mechanismwith or without succession and noninterference features (such, for example, as in a well-known type of fire alarm street box) and other of which sub-stations are equipped with mechanism for audibly and visibly manifesting alarms, such, for example, as the equipment ordinarily provided for such purposes at fire stations.

In such signaling systems, signals of primary importance are transmitted telegraphically, as by the formulation of code signals characterizing the various street boxes, the importance of which is such that they should be given right of way over all other signals. On the other hand, operating conditions frequently render it desirable to provide for conducting communication between sub-stations and the main station, or between one sub-station and another, as when the fire department OillCGlS have occasion to communicate from a street box with the firemen at some fire house, or to communicate with the main station for the purpose of summoning an ambulance, fuel wagon or other accessory equipment; as well as for the purpose of ascertaining the need of diverting fire fighting apparatus from one location to anotheras when additional fires occur while all or a large portion of the lire figating equipment of the community are engaged at some one fire.

It has also been found that when defects of any kind develop in such fire alarm circuits, it is very'desirable that means shall be available whereby an inspector or repairman may communicate with headquarters over a fire alarm circuit and that, for such purpose, calls for telephonic communication may be sent over any circuit without thereby causing response of the alarm apparatus therein.

Because of the fact that persons who send calls over fire alarm circuits are usually laboring under such a degree of excitement as to render it impracticable to rely upon them to excercise discrimination as to whether the circuit is already in use, it has been found to be essential that such circuits shall at all times be maintained in condition for the transmission of alarm signals andin most casesto provide so-called non-interference and succession mechanism whereby simultaneous or concurrent attempts to transmit alarm signals from two or more stations will result in complete and correct transmission of the signals of each of such stations Without further action on the part of those using them. It is therefore important that means provided for making telephonic calls and conducting telephonic communication shall not so alter the condition of such alarm circuits as to impair their availability for alarm transmission or so as to functionally affect non-interference and succession mechanism or in any way delay intended alarm transmission.

It is an object of this invention to provide a signaling system in which the usual telegraph signaling instrumentalities will be supplemented by the provision of facilities for transmitting telephonecall signals and for conducting telephonic communication without thereby at any time impairing the effectiveness of the system for alarm transmission.

It is a further object of this invention to provide such a system in which the telephonic calling and communicating facilities may be utilized without affecting the functional characteristics of non-interference and succession mechanism at street boxes or the noirinterference and repeating mechanism provided between circuits at the main station, when such a system employs two or more circuits.

It is a further purpose of this invention to provide such a system in which facilities are provided for readily establishing telephonic communication between circuits without impairing or altering the functional relationship of such circuits as to telegraphic alarm signals.

T It is a further object of this invention to provide such a system which embodies, for the accomplishment of the various telephonic calling and communication functions,

MASSACHUSETTS, ASSIGNOR TO THE well-known forms of apparatus which are readily obtainable both for initial installation and -for repairs and replacements.

In order to facilitate comprehension of this invention, an illustrative embodiment thereof is diagrammatically indicated in the accompanying drawing, in which like reference characters refer to similar parts.

That portion of the signaling system which is preferably located at the main station is enclosed by dotted line a, portions suitable; for locating in fire stations are enclosed by dotted lines Z), Z) and portions sig- 22, subject to non-interference and sucros sion control by mechanism (not shown) which mechanism is arranged for response to the electromagnct 23 in a manner well understood by those skilled in this art; together with theusual shunt switch 2d, sounder -25 andcalling key26. A shunt switch may also be provided, iii-accordance with ordinary practice, whereby the sound-er plied thereby which bears such relation to the normal resistance oi said circuit as to assure and key 26'will'be short-circuited while the door of the box is closed, and whereby such short-circuit will be interrupted when the door is open, affording acces. to said hey. As such a switch forms no part of this invention, it is omitted from the drawing in the interest of clearness and simplicity of disclosure. v

Such street boxes are diagrammatically shown as being serially connected in a normally closedcircuit (hereinafter referred to as a box circuit), which circuit leads to the main station and there includes telegraphic signaling means comprising the elec troinagnet 27 of the repeating mechanism P, manifesting means such the bell M and current Supply mechanism such as the battery Q. Although only two such boxes are shown in the accompanying illustration, it should be understood that any desired number of such boxes may be serially connected insuch a circuit. and that additional box circuits may be similarly connected to the main station.

The repeating mechanism P may, 'for ex ample, be of a type such as is shown and more fully described in Patent No. 810,912, dated January 30, 1906, which mechanism has circuit; controlling means comprising the pens 30 and 31 and an insulated cylinder 32 which carries a contact plate 38 arranged so that, during normal positioning ofsaid cylinder, saidplate will be situated in contact with the free ends of said pens, and so that, during a portion of each rotation of said cylinder, said plate will be carried out. of contact with said pens.

sociated transfer switch may be provided Said transmitter at the main station. be of any well-known type which is suited for being manually set to transmit desired code signals, and is so associated with said transfer switch TS that the transmitterl may be connected in either of two box =cir-.. cuits to control the repeating,mechanism, therethrough, to the end that codesignals may be transmitted therefrom-.through,the

repeating mechanism P to the vlire stationh circuits. The signaling key 86 may be sociated with the transmitter l 'assupple mental means for transmittin such ,code

signals.

The battery Q is arranged to apply an. electromotive lorce to the box circuit supnormal current iiow therethroughoi n'otless than some predetermined intensitysuch, for example, as milliamperes. motive force of the battery Q is correspondingly adjusted "ith relation to the normal resistance of the fire station circuit supplied 1 thereby so as to causecorrespondingly suitable normal current flow therethrough. The electromagnets of devices which should be responsive to the current flow incident A to the formulation oi telegraphic signals l- M, the repeating therein, such as the be mechanism P and registers R and R, as well as the street box electromagnets 23, are ar ranged for effective energization upon current flow through the windings thereof which is, say at least sixty per .centoi the The elect-rd intended normal current flow in the circuit" in which they are respectively included; andshould be arranged for functional. deenergization, following effective energization, whenever the current flow through the windings thereof is decreased to an intensity less than, say twenty current flow. Arrangement of such mag-v nets so thate'fl'ective energization thereoi will occur at an intensity substantially less than that oi the intended normal flow is provided for the purpose of affording a suit able factor of safety in accordance with ordinary practice in such systems; and the arrangement of such magnets whereby functional deenergization will occur prior to com:- plete cessation oit' current flow through the, windings thereof is correspondingly proper cent of such normalv vided for the purpose of assuring response by the mechanism controlled by such magnets when an attempt is made to break the circuit at a point at each side of which there is sufficient leakage to permit slight current flow.

A signaling system comprising no more than the instrumentalities and arrangement thus far described would provide a typical fire alarm system, the operation of which is well-known to those skilled in this art, and therefore will not be here described in further detail.

In applying this invention to the fire alarm system just described, in the manner indicated by the accompanying drawing, means is provided at each station for effecting telephonic communication. over the circuit or circuits associated therewith. Such means comprise call initiating and manifesting mechanism, telephonic transmitters and receivers and switching mecha nism for bringing said transmitters and receivers in operative association with their associated circuit. It will be noted that one or more portable telephone sets such as the set D, should be provided for use in connection with street boxes such as the li xes C, C; each of which sets should include means, such as the split plug 74, whereby such set may be connected in parallel with the current path through any box from which it is desired to establish telephonic communication.

The call initiating mechanism of each station comprises a normally closed current path of comparatively small resistance, in which path a calling key is provided for interrupting same when it is desired to initiate a call; together with a resistance shunted around such path, which resistance is so proportioned to the resistance of the entire circuit with which it is used that, when the calling key is open, the currenttiow in such circuit will be reduced from normal to an intensity such as will cause response of call manifesting mechanism, as hereinafter more fully explained, without so reducing such current flow as to cause functional deenergization of the electromagnets of devices which should be responsive to the current flow incident to the formulation of tele graphic signals. If it is desired to prevent interruption or mutilation of any telegraphic signal by the use of any calling key, each of such resistances should further be so proportioned to the resistance of the circuit in which it is included that, when the associated calling key is open, the current flow in such circuit will not be so reduced as to prevent effective energization (after a break of the circuit) of any of such electromagnets.

At the street boxes C and C, the call initiating mechanism shown comprises the telephone set D and the key 26, as hereinafter more fully explained; the call initiating means'provi-ded for each circuit at the main station comprises a resistance which is normally shunted by a closed circuit jack, as, for example, the resistance 49 associated with the box circuit and normally shunted by the jack 67, together with a plug 69 so associated with a normally closed key 26 that, when said plug is inserted in any one of said jacks andsaid key is thereupon opened, the current path of the circuit represented by such jack, will be interrupted, thereby rendering such resistance effective for suitably diminishing the current flow in that circuit; and, in the fire stations B and B the call initiating mechanism comprises resistances d9, included in the associated circuit, which resistances are shunted by normally closed keys 26".

In order to provide a suitable factor of safety, it is desirable that resistances forming part of call initiating mechanism, such as just described, shall be so proportioned to the normal resistance of the circuits with which they are associated that the cycles of change in the intensity of current flow in such respective circuits incident to alternate breaking and closing of the shunt circuit around any one of such resistances will extend from a minimum which so exceeds the maximum of the cycles of change in intensity of current flow which constitute tele graphic signaling impulses, as to afford a suitable factor of safety. For example, in a circuit wherein such telegraphic impulse cycles extend from a maximum of not less than sixty per cent to a minimum of not more than twenty per cent of normal current flow, in order to assure corresponding cycles of effective energization and functional de energization of such magnets, a desirable factor of safety for telegraphic signals might be afforded by so proportioning resistances such as the resistances 49 and d9 that, alternately breaking and closing the shunt around any one of such resistances will cause cycles of change in intensity of current flow in the associated circuit, which cycles will extend from a minimum of not less than sev-, enty per centof normal intensity.

The telephonic call manifesting mechanism provided at the various stations is arranged for response to cycles ofchange in the intensity of current flow from a maximum which may be somewhat below normal intensity to a minimum not greater than the minimum intensity of the cycles of change resultant from alternate breaking and closing of any one of the call initiating keys in such circuit. In. order to afford a factor of safety, it is desirable that such manifesting mechanism shall be responsive to cycles of change of intensity in current fiow which extend from a minimum somewhat in'excess ill) Art?

of the. aeyclescf change which result from alternate breaking and closing of the shunt around anyone-of such resistances. For

example,.it' the ininiinunicurrent flow incident to such telephoniccall cycles-is seventy per- :cent of normal intensity, such manifest ing..mechanisin might be arranged to act in response' to'cycles extending from a inininiuinof not more than seventy-five per cent of normal. In the illustrative embodiment of this invention shown by the drawing, the telephonic call manifesting mechani m orovided-at the street-boxes C consists oi the soundersfio, 25 that at the main stationwcomonsese-icr each-box or fire station cirouit,a relay (such as-the relays 66- and 66 together-with 'a lamp (such as the lamps 70 :a'ndTO'), relay: 71 and. buzzerfi? so associatedwtherewith that, upon functional de 81161giZ21tlO'11:0f anyone of such 18lZtf/S,'ltS associated'lam-p will helighted, the relay 71 will be efiectively energized and the buzzer 72iwill sound; and, that at the fire stations B andB?comprises-the Sounders 25?, 25".

The telephonic transmitters and receivers,

together-with the switching mechanism asso--- ciated therewithat-the Various stations is S0':L'l-1'L -1g6Cl--tl121t,Wlllle in use, each transresistance; the resistances bri get by transmitters being such-that variationsun the resistance of anysuchtransmitter willn-ot undulyaafi'ectthe intensity of the telegraphic 'sig-nalingcurrent flow in tliei circuit with which. it is associated, and the resistances bridgedacross =-such receivers having such inductance'as to cause practically all alter.-

nating current of telephonic frequency topass-t-hrouglr the receiver; i Thus in the telephonesetl), provided tor use in association with-signal boxes such as the boxes C, C,

a current path is provided from-one side of the split plug 7%, through the transinitte".

75 anclwthe-recei-ver T 6 in series, to the other side of said plug; a switch S being .so connected that, when closed, it willshort-circuit=thetransmitter '7 5 for a purpose which will be hereinafter more fully explained; at

the main station A, thetelephone transmitter '4:O-lS supplied by the battery Q acting.

parallel with the windings'oi the electromagnet: 27 of the repeater P, the relay 66 and the bell M associated with said circuit; and, in the instance of the tire station circuit, the normally open jack Get. is connected parallel with the relay 66' and registeiz 7 it associated with said circuit; to the end...

that insertion of any one the plugs 68,- 631" or 63, G3, in the jack 6% or the jack -64,

L, will establish operative association the- I70 during appropriate positioning of the key,

tween the transmitter 4-0 and receiver 41 tli'itltlle circuit of such jack 6% or 6%, as

the case may be; and, in th-e fire stations B and B, the transmitter 40 is connected in parallel with. the resistance 50 and-'tliez receiver 41. is arranged for connection in.

aara'llel with the-sounder 25 switch S is in theposition which it ocwhen the cupies when the receiver 41 has been removed "from the automatic hook e2. will be noted that a switch S is associated with the transmitter 40 andreceiver ll at the main station, for atrtiines cutting the F battery'Q, off from the: transmitter 40' and a opening the circuit through the receiver d1, in accordance WVltll ordinary practice.

Normal current pat-71s;

The normal current paththrough theibox i.

circuit shown, is as follows: troinwone side:

01" the battery Q through conductor 81, bell.f.

li'l, conductor 82, and a portion of there-- peating mechanism P including onset the electroinagnets 27, thence through conduce tor 83 to one terminal of street box C, thence through the key 26, sounder 25 and the.

telegraphic signaling Inechanisni comprisiiig tl e'magnet 20, contacts 21 and the shunt switch 24 to the other terminalsofsaid. b021,.

thence through conductor 8% to and correspondingly through streetboXC" and any other boxes similarly connectedin said cir-.

cuit, and through conductorhsfi, to and through relay 66 to-parallel cu rent. paths. one or which includesv the 'IGSlStflllCS 4:9 and.

of which includes the ClOSetlrClla.

the ot ier cuit jack 6", thence through conductor .88

to th transfer switch-TS and,.when said to the other side of battery Q The normal current iiathithrougli. the firen.

.110 switch is in the position sho wn,serially. through, the. contacts of transmitter T and therlrey 36; thence through conductor 89' station circuit, as shown, is as follows: from one side oi the battery through conductoi 90 and a portion of the repeatingxmechanisin P lRClP-Illllg one pair oi the pens30 and Y31 and their associatedplate 33, thence through conductor 91 to and through the.

magnet winding of the sounder no at the oi whichincludes theresistancett), another or which includes the contacts 43 and l i of station E, to parallel current pathsone.

theYswitclrS, and. the other of which 'in .x eludes the transmitter 40, thence through,

register R to parallel current .pathsone of which includes the resistance '49" and the other of which inchidesthe calling-whey and closed 26", thence through conductor 100 to and correspondingly through the instruments at station B and any other similarly equipped stations in .said circuit, and through conductor 101 to and through relay 66 to parallel current paths one of which includes the resistance 419 and the other of which in cludes the closed-circuit jack '67, thence through register R- to the other side of the battery Q",

Operation.

If, when a signaling system such as that shown by the drawing is in normal condition, it is desired to establish telephonic communication from a street box such as the street boxes C, C, with the main station,the split plug 74 of a telephone set such as the set D should be so inserted between the terminal plates of such box, as to connect said telephone set in parallel therewith, the switch S of such telephone set should then be manipulated so as to shortcircuit the transmitter 75 while the calling key 26 of such box is alternately opened for a desired number of times. Each time said key is so opened, the resist ance of-the telephone receiver 76 will be effectively included in the circuit, thereby serving to sufficiently diminish the current flow therethrough to cause the relay 66 to close the circuit through the lamp 70, thus lighting said lamp. The current flow incident to the lighting of the lamp 7 O, as just described, will cause the relay 71 to establish a current path through the buzzer 72, as follows, from one terminal of battery Q to the armature and contact of relay 71, through buzzer 72, serially through normally closed contacts 106 and 107, and 108 and 109 of key L, to other side of battery thus causing said buzzer to sound. Vhen the sounding of this buzzer has at tracted the attention of the main station operator, he will be enabled to answer the call by inserting one of the plugs 63, 68, or one of the plugs 63, 63, into the jack 6% and so operating the key L as to connect the plug so used with the operators telephone set comprising the transmitter a0 and the receiver 11. For example, if one of the plugs 63,

lie of the key L should be moved to the left, as shown by the drawing, thereby moving the contacts 110 and 111 into engagement with the contacts 112 and 113, respectively, and, at the same time moving the contact 108 out of engagement with the contact 109, so as to interrupt the current path through the buzzer 72. The operator may thereupon remove the receiver 11 from its associated automatic hook 12, thus permittin the contacts 53 and 55 to move into :1 engagement w1th the contacts 5 1 and 56,

respectively. Upon engagement of the an- '6 1, as just described,

63 is so employed, the han tomatic hook contacts as just described, a current path will be established from one side of the battery Q, through retardation coil 61, contacts 53 and 54, transmitter iO, and the primary winding of the induction coil 59, to the other side of said battery; and a telephonic current path will be established from one side of the one of the plugs 63 which is situated in the jack 64, through one of the condensers 62, through contacts 112 and 110, through secondary of induction coil 59, through contacts 55 and 50, through receiver 41, through contacts 111 and 113, and through another of the condensers 62 to the other side of said plug. From the that the receiver 11 and the secondary of he induction coil 59 will now be connected in parallel with one of the electromagnets 27 of the repeating mechanism P, the bell M, the battery Q], lay 66 so that telephonic communication may be carried on between a person using the telephone set D at the street box from which the call originated and the operator at the main station.

If, as a result of such conversation or otherwise, the operator at the main station desires to place such box c1rcu1t 1n communication with the fire station c1rcu1t,

this can be accomplished by inserting theother of the plugs 63, 63 in the jack 64, inserting the plug 69 in the jack 67, and thereupon operating the calling key 26'. When such plug 63 is inserted in the jack cuit of the operators set comprising the transmitter 10 and receiver 11, and the box circuit from which the call originated will be connected in parallel, through certain of the condensers 62, with each other and with the relay 66, register R and battery Q, of the fire station circuit. The condensers 62 are provided in such parallel connections so as to permit currents of telephonic frequency to pass from one circuit to another without establishing any directcurrent connection between such circuits or altering in any manner the functional relationship of such circuits as to telegraphic signals. Upon each break of the calling key 26, while the plug 69 is in the jack 67, as just described, the shunt around the resistance 49 will be interrupted, thus causing diminution of current flow in the fire station circuit, as hereinbefore more fully explained. Upon such diminution of current flow in said circuit, the sounders 25 of the stations B and B will act, and the manipulation of the key 26 in accordance with some predetermined code may cause said sounders 25 to manifest a signal which will be recognized as the specific call for one of such stations. In response to such call, the receiver 1 at the station foregoing it will be seen and the winding of re-' the telephonic cir-t "so called may be removed from its hook 42, tion and causing responseof the call mani- -therebypermitting the contacted to move away tromthe contacts?) and the contact 45 to move into engagement With the contact e6; so as to break the shunt which had "previously been effective between the con tacts 43' and 4% around the transmitter 40, and to connect'the receiver 41" in parallel With-the sounder 25 at such station.

' From the foregoing it Will be apparent that, While conditions are as just described, conversation addressed, to either the transmitter 40, the tra-nsinitter 40 or the trans m'itter 75-WVlll be reproduced bythereceivers 1541, 41 and 76; and-that, notwithstanding the conditioning'oi these circuits for telephonic' connnunication f sutiicient currentflou evill be maintained therein so=-=that ii the -telegra phic transmitting mechanism of 'one' of 'the boxes C, C is-set in motion," the bell* M wi'llrespondto the signal of suchbox and the repeatingmechanism P 'Wlll act-:in.

response thereto to cause manifestation of such-=signal"by the register R the main station and by the registers R R5 at fire stations Band B. lt'will also-be apparent that it, When it isdesired to establish telephonic communicationtrom one oi 'the boxes G, C, atelegra phic signal is in courseot: transmission fronr another o-tsuchboxes or from the transmitter T atthecentralotiice, notice thereofivill be given by the sounderQ at sueh street boxg so that the transmission of the telephonic call may be deferred until 355 the completion" o1 suchtelegraphic signal. Ifanyresistance whichtis, in effect, inserted in the linewhen initiating a telephonic call,1

is not 7 so proportioned" to the 1 to ta-l normal resistance-oi the circuit as to avoid d-imi-nueo' -tion or current 'flow below the intensity needed for thefleffective transmission'and -mani-testation ci -telegraphicsignals, 1 as hereinbefore more fully explained, those fivho ha-ve occasi'on tofisend telephonic calls sho'uldfbe' warnedto observe the associated sounder '25 before attempting to send a telephonicicalli an'd to defer sending such call it the SO'UllClGI' indicates that a telegra phic signal 1's in the'courseof transmissionand,

in any'event, it is preferable-that telephonic calls shall not lie-made whenthe-associated sounder is acting, even ii -such {ICUOII is in response to -another telephonic call, in view of the tact'that effective concurrent inc-lusion of twocalling resistances-in the same eirc'uit'might reduce current flow therein be- Ion/"thatat Which the transmission and manitestation ottclegraphic signals is as sured. Itit is desiredto telephonically call the mainstation trom'one ofthe fire stations B, B", the cal ling 'ltey 26 at such station should be opened, thereby effectively including the resistance 49" at such station inthe circuit leading theretrom'to the main stafesting relay .66 atthe main station in a manner correspondingto that hereinbetore described in greater detail in connection with a call'trom one-of the street boxes C, C. 1 Likewise, if itis desired-to send a telephonic call from the main station to one of the street boXesC, C,this may be accomplished by inserting the plug 69 in thejack 6T, whereupon the sounder-s" 25 may" be caused to act. In this connection, it Will be -understood by-those skilled in this artthat it'so-c-alleddoor shunts are provided: at .the street-boxes-Q C, sounders in such .boizeswill act in response'to such a call only at a boner boxes the door or doors oi which are open.

= It Will 't'urtherbe obvious to those slrilled lyl appurentthat the-number of street box circuits andiire station circuits may beincreased at ivill, andthat the system shown --bythe accompanyingdrawing and herein before described in detail: is merely illustrat-ire' of this invention; as various changes in be madev in the ,con'struction andan rangement shown-and described in detail -Without departing: from the scope o't-this (P invention. 7

l Jhat I claim and-desire to secure by- Let --ters Patent-of the United States of America. is:

1. "In a combiued telegraph and telephone 'signa ling systemuhaving main 1 and sub-,

stations and circuits each-serially connecting a respective one or: more of saic. sub-stations with saidmain station'wand current supply mechanism arranged for normally causing "suitable current flow in'each ot said cir- 'cuits; telegraphic signaling means com prising,code signaling mechanism adapted for conditioning associated circuits toeffect cycles of change between predetermined limits in the intensity of current tlow'therein repeating mechanism at saidniaiirsta tion having electrom agnet'c mechanism ar- "ranged for functional response: to the' 'a'tore said cyclesfot circuit condition and involving circuit controlling means arranged" to for said circuits, manifesting means havingelectron neticmechanism arranged tor functional response to such cycles of'circuit condition, and non-interference mechanism responsive'to the aforesaid cycles ot'circuit coneition for controlling functional operation of said code signaling mechanism;.'and means for ei'i'ect-ing telephonic communication over circuits between said stations compris ing,call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, said manifesting mechanism including means at said main station for indicating circuits in which calls originate, telephone instruments at said main and sub-stations, said instruments at certain of said sub-stations including a tele phone receiver of such resistance that the circuit associated therew'th may be so conditioned by serially including said receiver therein as to effect such second named cycles, together with means for so including any one of said receivers in an associated circuit and for operatively associating said ments and circuits, means at other of said stations for correspondingly conditioning the circuits respectively associated therewith, and means at said main station whereby said instruments thereatmay be operatively associated with either or both of any two of said circuits and whereby any two such circuits may be operatively associated with each other for telephonic communication therebetween, association of said telephone instruments with said circuits being effected by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism.

2. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits: -telegraphic signaling means comprising,-code signaling mech 'iism adapted for conditioning associated circuits to effect cycles of change each involving not less than a certain predetermined reduction in the intensity of current flow therein, repeating mechanism at said main station having electromagnetic mechanism arranged for func tional response to'the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate cor"- responding cycles in other of said circuits, manifesting means having electromagnetic niechanisn'i arranged for functional response to such cycles of circuit condition, and noninterference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising, call manifesting mechanism arranged for instru-- functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, said manifesting mecha nism including means at said main station for indicating circuits in which calls originate, telephone instruments at said main and sub-stations, said instruments at certain of said sub-stations including a telephone re ceiver of such resistance that the circuit associated therewith may be so conditioned by serially including said receiver therein as to effect such second named cycles, together with means for so including any one of said receivers in an associated circuit and for operatively associating said instruments and circuits, means at other of said stations for correspondingly conditioning the circuits respectively at said main station whereby said instru' ments thereat may be operatively associated with either or both of any two of said circuits and whereby any two such circuits may be operatively associated with each other for telephonic co-mn'iunication therebetween, such association of said telephone instruments with said circuits being effected by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism.

3. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits; telegraphic signaling means co1nprising,-+ devices having electromagnetic mechanism arranged for functional operation in response to cycles of change between predotermined limits in the intensity of current flow in one of said circuits thereat and mechanism for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding eonditioning of other of said circuits; and means for effecting telephonic communication over circuits between said stations comprising call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, said manifesting associated therewith, and means mechanism including means atsaid main "station for indicating circuits inwvhich calls 1 originate, telephone instruments at said 'iidevices. shaving electromagnetic mechanism a main and sub-stations, means. atv said subst tions for operatively associating said in strnments and circuits, and means at said main station whereby said instruments thereat may he operatively associated With either or both 01 any tivo of said circuits and whereby any two such circuits may be operatively associated with each other for tele phonic communication therehetween, association of said telephone instruments with said ci ving respective onesioitisaid instrumentsdn its being eiiected'hy s :connect shuntivith.n'indings; of certain ofsaid eleca-tromagnetic mechanisms as to-inaintainscircuit conditions suited for complete intended vi unctionina' ot I said telegraphic signaling means and said call manifestingmechanism,

and involving; mechanism for condi bion- 111g such circuits,respectively, as to effect such second named. cycles therein.

L-In acombined telegraph and telephone signaling system having main-and1sub-sta tions and circuitseach serially connecting a respective one or more of saidsub stations 7 With said main station. and :current supply mechanism arranged for. norn'ially causing suitable current flow in each of said circuits; :.tel.egraphic signaling means comprising,

arranged for functional operation in response to cycles of change in the intensity of :current tloivin one-of saldzcircuits thereat each involving not less than awpriedeter- ,.mined reduction in such intensity and mechanism for conditioningrespective asso- .ciated circuits to effect such cycles therein, a 40 said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning oi certain of said circuits to causecorresponding con-- ditioning of other of said circuits; and means .t'or etiecting telephonic communica tion over. said circuits between said stations comprising,call manifesting mechanismarranged forfunctional responseto cycles of change each involving not less than a predetermined reduction in'the intensity of current -fioW in said respective circuits which .last named reduction is less, extensive than said first named reduction. said manifestin ZJ mechanism including means at said main station for indicating circuits; in which calls originate, telephone instruments at said v main and sub-stations, means at said substations for operatively associating said in struments and circuits, and means at said main stations whereby said instruments thercat may be operatively associated with either or both of any 'twoof saidcircuits and whereby any two such circuit-s may be operatively associated with each other for telephonic communication therebetween,

i association. of said telephone. instruments with said circuits beingefiected by, so connecting respective ones of said instruments in shunt With windings of certain, of said electromagnetic mechanisms as: toinaintain;

circuit conditions suited for completeintel nphic signaling meanscomprising, cev-io arranged for functional operation ine to cycles of change between predelimits in theintensity'o1 current in or? said circuits thereat andmechill for conditioning"respective associated ci ults to ei fect aphic signaling means; including reto such conditioningofcertain 0t Ql'ClHtS to cause corresponding condieii ecting telephonic communicationover circuits between said stations compris- --call manifesting mechanism arranged i'esnective: one ormore oi": said sub-stationssuch cycles therein, said L oiiing of other of said circuits; and means for functionalresponse to cycles ot-cha-nge in the'intensity of current flow in saidre' spective circuits extending abovethe range l first named cycles and during each of which cycles such intensity is reduced to less than edeterinined value, said manifesting mechanism including means at said main station for indicating circuits in which calls originate, telephone instruments at said main and sub-stations, means at said substations for operativelyassociating said instruments and circuits, and means at said main station whereby said instruments thereat may be 0peratively associated With either or both-of any two of said circuits and whereby any two such circuits may be operativelyassomated with each other for 'iLGlGPllOIllCCOHk mnnicatio-n therebetiveen, association of said telephoneinstruments with said circuits beso eff cted as to-maintain conditions therein suited for complete intended functioning involving meclianisin forso conditioning such circuits, respectively, as to efiect such second named cycles therein.

- 6.v In a combined telegraph and telephone signaling systemhaving main and sub-stations and circuits eachserially connecting a respective one ormore of saidsub-stations withsaid main station and current supply mechanism arranged for normally causing of said telegraphicsignaling means and said call inanitesting mechanisnr, and

suitable current flow in each of said circuits; -telegraphic signaling means comprising, devices arranged for functional operation in response to cycles of change in the intensity of curr vat flow in one of said circuits thereat each involving not less than a predetermined reduction in such intensity and mechanism for cond tioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for e ecting telephonic communication over said GliCllliS between said stations comprising,call man'festing mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, said manifesting mecha nism including means at said main station for indicating circuits in which calls originate, telephone instruments at said main and sub-stations, means at said sub-stations for op'cratively associating said instruments and circuits, and means at said main station whereby said instruments thereat may be operatively associated with either or both of any two of said circuits and whereby any two such circuits may be opei'atively associated with each other for telephonic communication therebetween, association of said teleone instruments with said circuits being so or ected as to maintain conditions therein suited for com ilete intended functioning of telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, r ectively, as to effect such second named es therein.

7. In a combined telegraph and telephone na ing system having main and sub-staions and circuits each serially connecting a "es ective one or more of said sub-stations with main station and current supply m arranged for normally causing ble current flow in eacn of said circs;telegraphic signaling means comprisi g,code signaling mechanism adapted for conditioning associated circuits to effect cycles of change between predetermined limits in the intensity of current flow there n, repeating mechanism at said main station ha ing electromagnetic mechanism arranged for functional response to the aforesaid cycles of circuit condition and involving circuit control in means arranged to formulate correspond cycles in other of said circuits, manifesting means having electromagnetic mechanism arranged for functional re-- sponse to such cycles of circuit condition,

non-interference mechanism responsive to the aforesaid cycles of circuit condition for control ing functional operation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles of change in the intensity of current How in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for operatively associating said instruments and circuits by so spective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for compete intended functioning of said telegraphic signaling means andsaid call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to efiect such second named cycles therein.

8. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connect-inn; a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normal y causing suitable current flow in each of said circu1ts;telegraphic signaling means conilQI1SlI1g,-C0d6 slgnaling mechanism adapted for conditioning associated circuits to effect cycles of change between predetermined limits in the intensity of current flow therein, repeating mechanism at said main station having electromagnetic mechanism arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulatecorrespond ng cycles in other of said circuits, manifesting means having electromagnetic mechanism arranged for functional response to such cycles of circuit condition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic communication over said ClTCLllLS between said stations comprising,call manifesting mechanism arranged for functional response to eye es of change in the intensity of current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for operatively associsting said instruments and circuits by so connecting respective ones of said instru ments in shunt with windings of certain of said eiec ron'iagnetic mechanisms as to maintain circuit conditions suited for complete connecting ren intended functioning of said telegraphic signaling means. and involving mechanism for so condition ng such circuits, respec' tive y. as to effect such second named cycles therein.

9. Ina combined te egraph and telephone signaling s stem having main and sub-stations and circuits each serially connecting a res ective one or more of said substations ith sa d maiii station and current supply mechanism arrancedfor normally causing suitable current flow in each of said circuits: -telegraphic si naling means comprising,-code signaling mechanism adapted for conditioning associated circuitsto effect cycles of change between predeter mined limits in the intensity of current flow there n, repeating mechanism at said main station having electromagnetic mechanism said respective circuits extending above therange of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, telephone instruments at: said stationstogether with means for operatively associating said instruments and circuits by connect-ing respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms, and involving mechanism" for so conditioning such circuits, respectively, as to effect such second named cycles therein.

10. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each-of said circuits;telegraphic signaling means comprising,code signaling mechanism adapted for conditioning associated circuits to effect cycles of change each involving not less than a certain predeterminedreduction in the intensity of current flow therein, repeating mechanism at said main stationrhaving electromagnetic mechanism arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate fOllQ- spending cycles in other of saic circuits, manifesting means having electromagnetic mechanism arranged for functional response to such cycles of circuit condition, and non interference mechanism re ponsive to the' aforesaid cycles of circuit condition for controlling functionaloperation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations compris ng,-call manifesting mechanism arranged for func tional response'to cycles of change each involving not less than a predetermined reduction in the intensity of current fiow in said respective circuits which last named reduction is less extensive than said first named reduction, telephone instruments at said stations together with means for operatively associating said instruments and circuits by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic sig naling means and said call manifesti' mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

11. In a combined telegraph and telephone signaling system having main and sub-sta tions and circuits each serially connect' 5 a respective one or more of said sub-stations with said main station and current suppl -r mechanism arranged for normally causii g suitable current flow in each of said circuits;telegraphic signaling means comprising,code signaling mechanism adapted for conditioning associated circuits to effeet cycles of change each involving not less than a certain predetermined reduction in the intensity of current flow therein, repeating mechanism at said main station having electromagnetic mechanism arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, manifesting means having electromagnetic mechanism arranged for functional 1 sponse to such cycles of circuit condition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising,-- call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined rcduction in the intensity of current flow in said respective circuits which lastna-med reduction is less extensive than said first named reduction, telephone instruments at said stations together with means for opera iii) tivel associatin said instruments and circ cmts oy so connecting respective ones of said iistruments in shunt with windings of ertain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

12. In a combined telegraph and telephone si naling system having main one suns-Lations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing current flow in each of said cir- -telegraphic signaling leans comprisode signaling mechanism adapted for oning associated circuits to effect cycles of char g each involving not less than a tain predetermined reduction in the intensity of current flow therein, repeating mechanism t said main station having electromagnetic mechanism arranged for function-- al response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycle in other of said circuits, manifesting means having electromagnetic mechanism t 1* imnctional response to such cycles of circuitcondition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, telephone instruments at said stations together with means for operatively associating said instruments and circuits by connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

lin a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connesotin a respective one or more of said o-s \tions with said main station and cursupply mechanism arranged for normally causing suitable current flow in each of said circuits ;-telegraphic signaling means ccmprising,-code signaling mechanism adapted for conditioning associated circuits to effect cycles of change between predetermined limits in the intensity of ourrent flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, manifesting means arranged for functional response to such cycles of circuit condition, and noninterference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional opcration of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising,- call manifesting mechanism arranged for functional respnse to cycles of change in the intensity of current flow in. said respective circuits extending above the range of said first named cycles and during each of vhich cycles such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for so operatively associating said instruments and circuits as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call marine-sting mechanism, and involving mechanism for so conditioning such circuits, respectively, to effect such second named cycles therein.

ii. in a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits,-telegraphio signaling means comprising,code sr filing mechanism adapted for condit oning associatet circuits to effect cycles of change between predetermined limits in the intensity of current flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition nd involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, mani festing means arranged for functional responsato such ycles of circuit condition, and non-interference mechanism responsive to the aforesaid cycles of circuit condi tion for controlling operafunctionai tion of said code signaling mechanism; and means for effecting telephonic communica tion over said circuits between said stations comprising-call manifesting mechanism arranged for functional response to cycles of change in the i tensity of current flow in said respective circuits extendingaoove the range of said first named cycles and during of which cycles such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for so operatively associating said instruments and circuits as to ilaintain circuit conditions suited for complete intended fun tioning of said tele 'c signaling means, and involving 11 for so conditioning such circuits, ecti ly, as to ellct such second named 1 ycles therein.

15. in a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations With said main station and current supply mechanism arranged for normally causing suitable current flow in each of said cireuits;telegraphic signaling means comprising,code signaling mechanism adapted for conditioning associated circuits to effect cycles of change hetiv en predetermined limits in the inten sity of current flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition and involving circ controlling means arranged to formulate correspond ng cycles in other of said cirits, manifesting means arranged for funcal response to such cycles of circuit con dition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic. communication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range of said first named l and during each of which cycles cycle" such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for operatively associating said instruments and circuits, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

16. In a combined telegraph and tele phone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said subtions with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits :telegra1t)hic signaling means comprising,code signaling mechanism adapted for conditioning associated circuits to effect cycles of change each involving not less than a certain )redetermined reduction in the intensity of current flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, manifesting means arranged for fun tional response to such cycles of circuit condition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling inechanfsm; and means for effecting telephonic communication over said circuits between said stations comprising-call manifesting mechanism arranged for functional response to cycles of change each involvi not ess than predetermined reduction in the intensity of curnt flow in said respective circuit which amed reduction isless extensive than 3t named reduction, telephone instrusaid stations together *ith means operatively associating said instruand circuits as to maintain circuit conditions suited for con plete intendedmeans con'iprising,code signaling nism adapted for conditioning associated circuits to effect cycles of change each involving not less than a certain predetermined reduction in the intensity of current flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, manifesting means arranged for functional response to such cycles of circuit counition, and noninterfcrence mechanism responsive to the aforesaid cycles of circuit condition for con trolling functional operation of said code sling mechanism; and means for effecting telephonic con nication over said circuits between said stations comprising,- call manifestingmechanism a1 'anged for functional response to cycles of change each involving not less than a predetermined reduction in the inter of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, telephone instruments at said stations together with means for so operatively ElSSOCioillR-fl said instruments and circuits as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means, and in CJI volving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

18. in a combined telegraph and tele phone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said substations with said main station and current supply mechanism arranged for normally causing suitable current flow in each. of said circuits ;telegraphic signaling means comprising,code signaling mechanism adapted for conditioning associated circuits to effect cycles of change each involving not less than a certain predetermined reduction in the intensity of current flow therein, repeating mechanism at said main station arranged for functional response to the aforesaid cycles of circuit condition and involving circuit controlling means arranged to formulate corresponding cycles in other of said circuits, manifesting means arranged for functional response to such cycles of circuit condition, and non-interference mechanism responsive to the aforesaid cycles of circuit condition for controlling functional operation of said code signaling mechanism; and means for effecting telephonic communication over said circuits between said stations comprising,-call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less eX- tensive than said first named reduction, telephone instruments at said stations together with means for operatively associating said instruments and circuits, and involving mechanism for so conditioning such circuits, res aectively, as to effect such second named cycles therein.

' 19. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits ;telegraphic s gnal means compr- 'ng,devices havelect omagnetic mechanism arranged for t? operation in response to cycles between predetermined limits in e is' y of current iiow in one of said ircuits tnereat and mechanism for condiioning re ective associated circuits to effect cles therein, said telegraphic signalincluding repeating n ec lanism at station responsive to such con- 1 certain of said circuits to cause conditioning of other of said circ s; and means for effecting telephonic communication over said ci-cuits between said stations comprising,-call manifesting mechanism fe uidisedre ponse to cycles of change in the intensity of current flow in said respective circuits extend ing above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetcrmined value, telephone instruments at s id stations together with means for operai vely associating said instruments and circuits by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

20. In a combined telegraph and telephone signaling system having main and sub-stations and circ its each connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current fiow in each of said circuits telegraphic signaling means c.omprising, devices having electromagnetic mechanism arranged for functional operation in response to cycles of change between predetermined limits in. the intensity of current flow in one of said circuits thereat and mechanism for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic communication over said circuits between said stations comprising,-call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, telephone instruments at said stations together with means for operatively associating said instruments and circuits by so connecting respective ones of said instruments in shunt with windings of certain 0? said electroma ne c mechanisms as to m intain circuit conditions suited for complete intended functioning of said telegra hic signaling means and invo ving mechanism for so conditioning such circuits, respectively, as to e fect such second named cyc es therein.

21. In a combined te egraph and te ephone s nalin system having main and sub-stations and circuits each connecting a respective one or more of said sub-stations with said main st tion and current supply mechanism arranged for normal y causing suita le ur ent flow in each of said. c rcu s;-

' first'named cycles and during telegraphic. signaling means comprising, devices having electromagnetic mechanism arranged for functional operation in response to cycles of change between predetermined limits in the intensity of current flow in one of said circuits thereat and mechanism "for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such condi ioning of certain of said circuits to cause corresponding conditioning of other oi said circuits; and means for effecting telephonic communication over said circuits between said stations comprising-- call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range or" said ah of which cycles such intensity is reduced to less than a predetermined value, elephone instruments at said stations together with means for operatively associat'ag said instruments and circuits by connecting respective ones of said instruments in shunt with ivindings of certain of said electromagnetic mechanisms, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

22. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each connecting a respective one or more of said sub-stations With said main station and current supply mechanism arranged for normally causing suitable current flow in each of said cir cuits;telegrapl1ic signaling means comprising,devices having electro-magnetic mechanism arranged for functional opera tion in response to cycies of change in the intensity of current flow in one of said circuits thcreat. each involving not less than a predetermined reduction in such intensity and mechanism for conditioning respective associated circuits to eitect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and'means for effecting telephonic communication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity oteur ent flow in said respective circuits which last named reduction is less extensive than said first named rcdrction, telephone instruments at said stations together with means for .operativelv associating said instruments and circuits by'so connectine" espective 0: es of said instruments in shunt" vvitll windingsof "certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles there n.

23. In a combined telegraph and tele phone signaling system having main and sub-stations and circuits each connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits;telegraphic signaling means comprising,-devices having electro-magnctic mechanism arranged for functional operation in response to cycles of change in the intensity of current flow in one o f said circuits thereat each involving not less the. a predetermined reductionin suchintensity and mechanism for conditioning respective associated circuits to effect such cycles therein,'said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of" said circuits; and means for effecting telephonic communication over said circuits between said stations comprising-mall manifesting mechanism arranged for functional re sponse to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduc tion is less extensive than said first named reduction, telephone instruments at said stat-ions together With means for operatively associating sait instruments and circuits by so connecting respective ones of said in struments in shunt With windings ot' certain of said electromagnetic mechanisms as to 'n'iaintain circuit conditions suitec for complete intended functioning of said te1egraphic signaling means, and involving mecha ism i i so conditioning such circuits, respectively, as to effect such second named cycles therein,

'24:. In a combined telegraph and telephone signaling system having main 4 sub-stations and circuits each connecting a respective one or in re oi said sub-stations vvith said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circu] ig teleg aphic s-i means compri ing,devices having eiectro-ma ic mechanism arranged for functional cration in response to cycles of change in the intensity of current flow in one of said cir cuits tliereat each involving not t n a predetermined reduction in such int mechanism 'forconditioning respecwe associated ecircuits to ettect suehcy'cies ill) therein, said telegraphic signaling means including reoeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic communication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles or change each involving not less than a predetermined reduction in the intensity of currentfiow in said respective circuits which last named reduction is extensive than said first named reduction, telephone instruments said stations together with means for operatively associating said instruments and circuits by connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms, and involving mechanism for so conditioning such circuits, respectively, as to eitect such second named cycles therein.

25. in a combined telegraph and telephone signaling system having main and sub-stations and circuits each connecting respective one or more 0% said substations with s; id main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits telegraphic signaling means comprising, devices arranged for functional operation in response to cycles of change between preless determined limits in the intensity of current flow in one or" said circuits thereat and mechanism for conditioning respective associated circuits to effect such cycles therein.

said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic communication over said circuits between stations comprising call manifesting mechanism arranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range oi? sail first named cycles and during each of which cycles such intensity is reduced to lets than a predetermined value. telephone instru ments at said stations together with means for so operatively associating said instruments and circuits as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditionsuch circuits respectively, as to effect such second named cycles therein.

26. in a combined telegraph and telephone signaling system having main and sub-stations and circuits each connecting a respective one or more of said sub-stations with ranged for functional response to cycles of said main station and current supply mechanism arranged for normally ca sing suitable current flow in each of said circuits gtelegaphic signaling means coin arisin devices arranged for functional operation 1 response to cycles of change between predetermined limits in tie intensity of cur rent flow in one of said circuits there-at and mechanism for conditioning respective alsociated circuits to eliect such cycles therein, said telegraphic signaling means includ r repeating mechanism at said main static i responsive to such conditioi oi cert of said circuits to cause corresponding conditioning oi other of said circuits; at 11': ans for effecting telephonic communication over said circuits between. stations coinprising.call manifesting mechanism arranged for functional response to cycles of change in the. intensity of current flow in Said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predeteiniined value, telephone instruments at said stations together with means for so oporatively as sociating said instruments and circuits to maintain circuit conditions suited for complete intended functioning of said telo-. grapnic signaling means, and involving mechanism.- for so conditioning such circuits, respectively, as to effect such second named cycles therein.

27. In a combined telegraph and telcpho signaling system having main and sub tions and circuits each connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits telegraphic signaling means comprising,- devices arranged for functional operation in response to cycles of change between predetermined limits in the intensity of cur rent flow in one of said circuits thereat and mechanism for conditioning respective associated circuits to eilect such cycle": therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding corditioning of other of said circuits; Zll'li means for effecting telephonic communication over said circuits between stations comprising,-call manifesting mocha ism change in the intensity or current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value telephone instruments at said stations together with means for ooeratively wsociating said. instruments and circuits and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

'28. In a combined telegraph and telephone signaling system having main and su stations and circuits each connecting a re spective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits telegraphic signaling means comprising,- devices arranged for functional operation in response to cycles of change in the intensity of current flow in one of said circuits thereat each involving not less than a predetermined reduction in such intensity and mechanism "for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station spousive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and ir ans for effecting telephonic corninuni ion over said circuits between said stations comprising,-call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, telephone instruments at said stations together with means for so operatively associating said instruments and circuits as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

29. In a combined telegraph and telephone signaling system having main and substations and circuits each connecting a respective one or more of said substations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said cireuits;telegraphic signaling means comprising ;devices arranged for functional operation in response to cycles of change in the intensity of current flow in one of said circuits thereat each involving not less than a predetermined reduction in such intensity and mechanism for conditioning respective assocta ed circuits to effect such cycles therein, said telegraphic signaling means includn repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic communication over said circuits between said stations comprising callmanifesting mechanism arranged for functional response to cycles functioning of said telegraphic signaling means, and involving mechanism for so conditioning such circuits, respectively, as

to effect such second named cycles therein.

30. In a combined telegraph and telephone signaling system having main and substations and circuits each connecting a respective one or more of said substations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits;telegraphic signaling means comprising,-devices arranged for functional operation in response to cycles of change in the intensity of current flow in one of saic circuits thereat each involving not less than a predetermined reduction in such intensity and mechanism for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic commu nication over said circuits between said stations comprising,call manifesting mech anism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current iiow in said respective circuits which last named reduction is less extensive than said f rst named reduction, telephone instruments at said stations together with means for operatively associating said instruments and circuits, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

31. in a combined telegraph and telephone signaling system having main and sub stations and circuits eaclserially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits;telegraphic signaling means comprising devices having electromagnetic mechanism arranged for functional operation in response to cycles of changebetween predetermined limits in the intensity of current flow in one of said circuits thereat and mechanism for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at-said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic communication over circuits between said stations comprising,-call manifesting mechanism ar ranged for functional response to cycles of change in the intensity of current flow in said respective circuits extending above the range of said first named cycles and during each of which cycles such intensity is reduced to less than a predetermined value, said manifesting mechanism including means at said main station for indicating circuits in which calls originate and responsive de vices each having an electroinagnet winding serially included in its associated circuit at each of certain of said sub-stations, respectively, telephone instruments at said main and sub-stations, said instruments at certain of said sub-stations including a receiver arranged to be connected in parallel with said elcctromagnet winding of said responsive device thereat and a transmitter shunted by a resistance serially included in its associated circuit and also normally shunted by a current path of comparatively low resistance, means at each of said certain substations for so connecting said receiver in parallel. with ing said shunt path around said transmitter, and means at said main station whereby said instruments thereat may be operatively associated with either or both of any two of said circuits and whereby any two such circuits may be operatively associated with each other for telephonic communication therebetween without altering the functional relationship of such circuits as to telegraphic signals, association of said telephone instruments with said circuits being effected by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended functioning of said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

82. In a combined telegraph and telephone i signaling system having main and substations and circuits each serially'connecting a respective one or more of said substations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits ;telegraphic signaling means comprising -devices having electromagnetic mechanism arranged'for functional operation in response to cycles of change in the intensity of current flow in one of said circuits thereat each involving not less than a predetermined reduction in such intensity and mechanism for conditioning respective associated cirsaid winding and for breakcuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsive to such conditioning of certain of said circuits to cause corresponding conditioning of other of said circuits; and means for effecting telephonic counnunication over said circuits between said stations comprising,call manifesting mechanism arranged for functional response to cycles of change each involving not less than a predetermined reduction in the intensity of current flow in said respective circuits which last named reduction is less extensive than said first named reduction, said manifesting mechanism including means at said main station for indicating circuits in which calls originate and responsive devices each having an electroinagnet winding serially included in its associated circuit at each of certain of said sub-stations, respectively, telephone instruments at said main and sub-stations, said instruments at certain of said sub-stations including a receiver arranged to be connected in parallel with said electromagnet winding of said responsive device thereat and a transmitter shunted by a resistance serially included in its associated circuit and also normally shunted by a current path of comparatively low resistance, means at each of said certain sub-stations for so connecting said receiver in parallel with said winding and for breaking said shunt, path around said transmitter, and means at said main station whereby arid instruments thereat may be operatively associated with either or both of any two of said circuits and whereby any two such circuits may be operatively associated with each other for telephonic communication therebetween without altering the functional. relationship of such circuits as to telegraphic signals, association of said telephone instruments with said circuits being effected by so connecting respective ones of said instruments in shunt with windings of certain of said electromagnetic mechanisms as to maintain circuit conditions suited for complete intended 'functioningof said telegraphic signaling means and said call manifesting mechanism, and involving mechanism for so conditioning such circuits, respectively, as to effect such second named cycles therein.

33. In a combined telegraph and telephone signaling system having main and sub-stations and circuits each serially connecting a respective one or more of said sub-stations with said main station and current supply mechanism arranged for normally causing suitable current flow in each of said circuits;telegraphic signaling means comprising,-devices arranged for functional operation in response to cycles of change between predetermined limits in the intensity of current flow in one of said circuits therecertain of said circuits to cause correspond at and mechanism for conditioning respective associated circuits to effect such cycles therein, said telegraphic signaling means including repeating mechanism at said main station responsiv to such conditioning of ing conditioning of other of said circuits; and means for efi'eetlng telephonic connnumeat on over said circuits between said stations vcomprising call manifesting rnechanisni arranged for functional response to cycles of change in the intensity of currentlioiv in said respective circuits extending above the range oi. said first named cycles and during: each oi which cycles such intensity is reduced to less than a ,predetei-inined yalue, said manifesting mechanism including'ineansat said main station for indicating circuits in which calls originate, telephone instruments at said main and sub-stations, said instruments at certain of said sub-statio s inclui'l ng a transmitter shunted by a resistance rally included in its associated circuit and also normally shunted by a current path of coinpa 'atively low resistance, means at rich of said certain sul'i-st-ations for brealzing said shuntpa'th around said tran mitter, and means at said niain station whereby said inst :unients there-at may he operatively associated with either or both of any two of said circuits and whereby any two such circuits may be oncrati-vely associated ivita each other for telephonic connnu- 'ui 'ation therebetivecn Without altering the functional ielationship of such circuits as to telegraphic signals, association of said teleione instruments with said circuits being is I) 0 t d as to maintain conditions the in or comple e inteudet. functionin or said telegraphic signaling means and said call. i'i'ianifesting' mechanism, and involving mechan sm for so conditioning such circuits, respectively, as. to effect such second named cycles therein.

lnacombined telegraph and telephone a lingg; system having main and suh-sta s and circuits each serially connecting a respective one or more of said sub-stations ,u'iith said rnain station and current supply mechanism arranged for normally causing sui able ciuitentflow in each of said 011'- ciuts.;telegraph1cVsignaling means comprising,devices arranged for functionaloperation in response to cycles of change 111 the station responsie lo such conditioning of certain cit said circuits to ca correspoir i g: condrtionuigg' of other of said circuits; and means: tor effecting teleplu'inrc communication over said circuits between said stations coiuprising.call manifesting mechanism arranged torluinztional response to cycles of change each involving not less than a predetermined reduction in the intensity oi? ,urrent flow in said respective circuits which last named reduc ion is less extensive than said first named reduction, said n'ianii'esting 7 mechanism iuclui'lingz' means at said main station for indicating circuits in which calls originate telephone instruments at said main and substations, said instruments at certain ot said sub-stations including a transmitter shunted by a resistance serially included in its associated circuit and also nonnally shunted by a current-path ot comparatively low resistance, means at each of said certain suh-v ions tor breaking said shuntpath around said trzuisniitter and means at said niain station whereby said instruments therea-tmaybe operatively associated with either or both of any two of circuits a d whereby any two such circuits may be operatively associated with each other for telephonic communication therebetiveen as sent altering the functional relationship of such circuits as to telegraphic signals, association of said telephone instruments with saic'circuit-s being so effected as to maintain conditions therein suited for coin elete'intended lunctioni-n9; of said telegraphic signaling means and said call inanitestingmechanism and involving mechanism for so conditioning' such circuits, respectively. as to etiect such second nained cycles therenn nnnnnnicic n-Pnncnnrcn. l 

